Home | My Profile | Contact Us
Research Trends Products  |   order gateway  |   author gateway  |   editor gateway  
Register | Forgot Password

Author Resources
 Author Gateway
 Article submission guidelines

Editor Resources
 Editor/Referee Gateway

 Regional Subscription Agents/Distributors
Trends in Photochemistry & Photobiology   Volumes    Volume 9 
Effects of humic substances in photoinduced heterogeneous redox transformations of pollutants in aquatic systems
Elena Selli
Pages: 87 - 96
Number of pages: 10
Trends in Photochemistry & Photobiology
Volume 9 

Copyright © 2002 Research Trends. All rights reserved


The role of humic substances in the sunlight initiated interfacial electron transfer reactions involving organic and inorganic pollutants in natural aquatic systems has been elucidated in the presence of stable semi-conductors as models of minerals with semiconducting properties. The following case studies are reported- i) the sunlight induced reduction of Cr(VI) (chromate anions) on ZnO, in which the sensitizing effect of humic acids was first demonstrated, occurring through either electron or energy transfer to the oxide; ii) the photoinduced reduction of U(VI) on titanium dioxide, investigated by time-resolved fluorescence measurements, in which the rate of the aqueous phase reaction was also enhanced by U(VI) complexation with humic acids, while a photosensitization effect on the interface reaction was evidenced only under high intensity irradiation, filtering effects prevailing at low irradiation; iii) the TiO2-mediated, sunlight induced degradation of tetrachloroethene. In this case humic acids decreased the rate of the major oxidative route leading to mineralization of the substrate and increased the rate of the reductive route leading to the formation of dichloroacetic acid, which also underwent oxidative photodegradation.

Buy this Article


Buy this article
Buy this volume
Subscribe to this title
Shopping Cart

Quick Links
Search Products
Browse in Alphabetical Order : Journals
Browse by Subject Classification : Journals

Ordering Information Ordering Information
Downloadable forms Downloadable Forms